Technical Field. This invention relates to an animal feed. The animal feed may be fed directly to animals, preferably ruminants, in granular or solid block form, or may be mixed with feed supplements, trace elements, protein meals, cereals, hay and/or the like.
Background: There is ever increasing interest in utilizing the by-products of agricultural processes to produce useful benefits. Such utilization of by-products which would otherwise be waste saves in two ways; it saves the cost of disposal of the by-product as waste, and it saves the cost of the useful product which the by-product can replace. One industry which has the need to find a use for its by-products is the sugar cane industry. The end products of sugar cane processing include ethyl alcohol for use as an industrial chemical, a gasoline substitute in automobiles, rum, sucrose or table sugar, and molasses.
Sucrose is manufactured by crushing sugar cane and placing the juice therefrom in pans which are placed in a vacuum. Under vacuum, water boils away from the sugar cane juice, and when the solution becomes saturated, sucrose crystals form from the solution. The liquid is removed from the crystallized sugar and placed in other vacuum pans and evaporated again. The second evaporation results in sucrose crystals forming from the solution. The liquid is again removed from the sucrose crystals and the liquid is evaporated under the vacuum a third time. The liquid remaining from the final operation is molasses. Thus, molasses is basically sugar cane juice with much of the sugar removed.
Sugar cane juice or molasses can be further processed by diluting it with water and fermenting it. In the fermentation process, the yeast utilizes the residual sugar in molasses as energy for their metabolism and produce ethyl alcohol, also known as ethanol, as a by-product. The fermented mixture of sugar cane juice or diluted molasses is typically distilled to produce a more purified form of alcohol. This can result in the production of rum, which is used for human consumption, or in the production of ethyl alcohol of very high grade for industrial chemical application, and ethanol which is used as fuel, or as an additive to gasoline.
The material left after sugar cane juice or diluted molasses has been fermented and distilled is known as stillage, Dunder, distiller's grain or slops. Since the yeast has utilized sugar in the fermentation process, there is little sugar left in the stillage or Dunder. In U.S. Pat. No. 3,983,255, Bass notes that "the fermentation residue or effluent--known commercially as slop, vinasses or Dunder, . . . Is almost invariably run to waste". Bass notes that after concentrating six to eight times, slop reaches a concentration of 60.degree. to 80.degree. Brix. This indicates that Bass believes the sugar content of slop is about 10%. This shows that the action of yeast has utilized most of the sugar in molasses, and produced ethanol as a by-product. By comparison, after the first extraction of sucrose crystals from sugar cane juice, the remaining liquid contains 65% sugar, the second extraction of sucrose from sugar cane juice contains 60% sugar, and the third extraction (or black strap molasses) of sucrose from sugar cane juice contains 55% sugar.
Besides sugar and ethanol, other by-products of sugar cane processing and molasses manufacture include acetic acid, citric acid, yeast, butanol, glycerol, dextran, aconitic acid, monosodium glutamate, bacteria, protein, oils, vitamins, other alcohols, fusel oil (a mixture of alcohol), glycerol, succonate, acetate, enzymes and organic material. By-products of the distillation process include stillage, Dunder, or slops. U.S. Pat. No. 4,160,041, Schroeder, at column 3, line 29, discloses that other by-products of the molasses and sugar industry include "Steffen's filtrate, a sugar containing by-product obtained from beet molasses. Another sugar industry by-product in (sic) Myces, which is the residue after separation of yeast cells grown in molasses culture medium".
For many years, the benefits of molasses in stock feeding have been well recognized. These include increased palatability, improved aroma, dust suppression, higher feed intake and extra energy. However, with few exceptions, the practical limitations of molasses inclusion in diets have been difficult to surmount. The major exceptions have been the feed lot industry and selected feed mills with spray line equipment for molasses inclusion to a maximum of typically 3% by weight (because of the difficulties of processing at higher inclusion levels).
Recognizing these advantages and disadvantages of handling the product, numerous attempts have been made to present the product in a free-flowing form. These systems have been based on the following techniques:
1. Microwave treatment of dehydrated molasses in a well-presented form--this suffers from hygroscopic absorption and is a costly addition to normal feed rations; PA1 2. Molasses mixed with copra meal--this is not suitable for mono-gastrics due to the high fiber percentage of the mixture; and PA1 3. Molasses blended with diatomite--the silica level is disadvantageous to nutrition. PA1 (a) Dunder, dunder and molasses, dunder and molasses by-products: 10-60%; PA1 (b) Bentonite: 10-80%; PA1 (c) Zeolite: 10-80%.
A solid animal feed supplement, comprising chiefly of molasses, whey, or a lignosulphonate, in solid block form, is disclosed in AU-B-19119/76 (505607) (PACIFIC KENYON CORPORATION). This patent discloses a feed supplement where the carbohydrate content is present at a concentration of from 45-93% by weight, and one potential source of the carbohydrate is molasses. The patent describes a supplement which requires the addition of solidifying ingredients (including a soluble phosphate or phosphoric acid) sufficient to solidify the supplement into solid block form. The method is not suitable for the production of animal feed in granular form.